Conventional devices, systems, methods, and processes pursue various approaches in an attempt to achieve optimum wound healing environments. The process of wound healing is complex and fragile. There are many different factors involved, including mechanical stress on the wound, debris in the wound, temperature of the wound, desiccation and maceration, infection, chemical stress, medications, and other physiological characteristics of the patient. Primary wound dressings include topical agents placed directly on the wound, while secondary wound dressings include dressings that cover the primary dressings and the wound bed.
One factor noted in the healing process is the temperature at which the wound undergoes optimal healing. It is believed that temperature controls the rate of chemical and enzymatic processes occurring within the wound, as well as the metabolism of cells and tissue engaged in the repair process.
Frequent dressing changes or wound cleansing with room temperature solutions to address the factors of debris, infection, and the like, also have the negative effect of reducing wound temperature. Whenever a conventional secondary wound dressing (such as bordered gauze) is changed, the wound bed is cooled with removal of the old dressing and with cleansing/irrigation of the wound bed. The molecular level body cells involved in the healing process (e.g., fibroblast, keratinocytes, cytokines, proteases, growth factor activity) slow down or halt function when their environment falls far below body temperature. Thus, wound dressings that promote a “cooling” effect may not support wound repair, and the process of replacing wound dressings promotes a cooling effect that also does not support wound repair.
There are conventional dressings that attempt to increase the wound temperature faster than bordered gauzes, once the dressing is in place. A bordered foam dressing provides more thermoregulation than bordered gauze. The foam brings the wound bed to optimal wound healing temperature faster, but there are negatives to the foam. Foam holds more wound drainage or other bodily excretions and therefore can keep the wound bed moist and potentially expose the wound to undesirable bacteria and the like. Some moisture is good at the wound bed, but too much moisture can make a wound deteriorate (and macerate the periwound tissue). In addition, prior attempts at dressings that promoted more rapid temperature increases of the wound included placing a metal foil sheet over the wound. While this had the desired effect of more rapidly increasing wound temperature relative to bordered gauzes, a shortcoming of this type of configuration is that wound drainage is hindered by the liquid impermeable foil, the opaque foil prevents observation of the wound through the dressing, prevents observation of saturation levels of any dressing wound contact surfaces that absorb wound exudates, and procedures such as strike through wound drainage cannot be visualized, thus hindering the implementation of such procedures.